WASHINGTON (Reuters) - A Columbus, Ohio, man who trained with Islamic militants in Syria has been arrested and charged with supporting terrorism and making false statements, the U.S. Justice Department said on Thursday.

Abdirahman Sheik Mohamud, 23, a naturalized American, had been instructed by a Muslim cleric to return to the United States and carry out an act of terrorism, a federal indictment said.

The indictment said Mohamud told an associate that he wanted to go to a military base in Texas and "kill three or four American soldiers execution-style."

Mohamud's brother was killed fighting with the Nusra Front, the Syria-based affiliate of al Qaeda, the indictment said.

Before leaving for Syria, Mohamud had posted material on social media promoting symbols of the Islamic State militant group, the indictment said. A law enforcement official said, however, that once in Syria Mohamud and his brother, Aden, trained with Nusra.

According to the indictment, Mohamud obtained a U.S. passport and purchased a one-way ticket to Greece. He left the United States in April 2014 but instead of flying to Greece, went to Istanbul, Turkey, and then Syria.

In Syria he sent videos of himself to an unnamed person, the indictment said. In one video, he pointed to a gun in a holster on his hip and in another, he stood in front of a white house with a black flag on it.

Upon his return to the United States, the indictment said, Mohamud told an unidentified person that while in Syria, he had been trained in shooting weapons, breaking into houses, using explosives and hand-to-hand combat.

According to the indictment, Mohamud also said that just before he was about to start fighting with militants in Syria, a cleric connected with an unspecified militant group told him he should return to the United States and "carry out an act of terrorism." A law enforcement official identified the cleric as a representative of the Nusra Front.

According to the indictment, Mohamud "wanted to kill Americans, and specifically wanted to target armed forces, police officers or any uniformed individuals." The indictment said Mohamud's plan was to attack a U.S. military base but that he also had a backup plan to attack a prison.

The indictment said Mohamud told his unnamed interlocutor that his brother, Aden, had died and that Mohamud himself "was next and would join Aden soon.

A U.S. official said Mohamud initially was arrested in February in Columbus and held by local law enforcement authorities. The official said Mohamud would be transferred into federal custody on Thursday.

(This story has been refiled to drop Islamic State reference from headline)